Technical Field
This disclosure is directed to electronic circuits, and more particularly, to circuits that perform level shifting and clock generation functions.
Description of the Related Art
Integrated circuits utilizing digital logic may include a number of circuits whose operation is synchronized to a clock signal. The types of circuits that operate according to a clock signal include flip-flops, various types of memory, counters, and so on.
As integrated circuits have become denser, clock signals have become faster (i.e., higher frequency). Furthermore, sequential circuits typically have timing budgets, which is an allotted amount of time in which to complete operations when a received clock signal is in a certain state. Furthermore, many clock signals operate according to a duty cycle, which is the amount of time within a single clock cycle that the clock signal is considered to be active (e.g., high) relative to the amount of time a clock signal is inactive (e.g., low). For example, a clock signal having a 50% duty cycle may spend half a cycle high and half a cycle low. Sequential circuits may be designed such that a single cycle's worth of operations are performed during the portion of a clock cycle that is active.